1. Field of the Invention
This invention relates to a new and improved plastic mask for use by dentists, surgeons, and others who may be contaminated with germs and viruses of their patients and customers. The mask is supported by a band which fits across the forehead and around both sides of the head above the ears and comprises an upper or visor part which is integral with or attached to the band and a removable, disposable transparent shield which snaps onto the visor and extends substantially vertically down below the level of the mouth of the wearer. The shield protects the eyes, nose and mouth of the wearer, but does not interfere with normal breathing. The visor is provided with a vent which may be opened and closed as conditions require. Coated on or otherwise applied to the shield is a filter to protect the eyes from ultraviolet, blue or other harmful radiation from instruments which are presently used by dentists in curing tooth-filling plastic.
2. Description of Related Art
Surgical masks of gauze and paper have been used by surgeons and sometimes by dentists to prevent intercontamination of the doctor and patient. However, wearing such masks is hot and uncomfortable and, frequently, frightening to patients. Putting the masks on and removing them are time consuming and often difficult. Breath condenses within the mask and the latter becomes saturated with moisture and thereby fails to be an effective barrier to viruses and bacteria.
Surgical masks cause the wearer to re-inhale exhaled breath causing the CO.sub.2 content of the blood to rise. The result of this may be increased heart and respiration rates and higher body temperatures and perspiration.
Safety face shields with vents, but of different construction include U.S. Pat. Nos. 3,152,588; 3,298,031; 3,678,929; and 4,250,477.
Detachable masks are shown in British Pat No. 503,750 and U.S. Pat. Nos. 1,279,884; 2,818,829; and 3,346,875. Mere face shields are shown in U.S. Pat. No. 2,978,709, for example.
Additionally, shields attached to eyeglass-type frames are shown in German Pat. No. 688,227; U.S. Pat. Nos. 1,582,164 and 2,774,970.